Cement Anchor Screws
The following information refers to the Tapcon brand cement anchor screw:
Standard Sizes
- Diameter - the cement anchor screw comes in two standard diameters of 3/16” or 1/4”
- Length – the 3/16” diameter comes in 7 standard lengths of 1-1/4”, 1-3/4”, 2-1/4”, 2-3/4”, 3-1/4”,3-3/4” and 4” the 1/4” comes in 9 lengths of 1-1/4”, 1-3/4”, 2-1/4”, 2-3/4”, 3-1/4”,3-3/4”, 4’, 5” and 6”.
Large Diameter Sizes
- Diameter- the large diameter cement anchor screws come in four diameters: 3/8”, 1/2”, 5/8” and 3/4”
- Length – each large diameter cement anchor screw comes in different lengths.
| Diameter | Length |
|---|---|
| 3/8” | 1-3/4” |
| 2-1/2” | |
| 3” | |
| 4” | |
| 5” | |
| 1/2” | 2-1/2” |
| 3” | |
| 4” | |
| 5” | |
| 6” | |
| 5/8” | 3” |
| 4” | |
| 5” | |
| 6” | |
| 3/4” | 4-1/2” |
| 5-1/2” | |
| 6-1/4” |
Coatings
The standard diameter cement anchor screw is coated with a blue Climaseal® coating to help rust resistance. The large diameter cement anchor screws are coated with a silver Climaseal® coating.
Head Types
The 3/16” and 1/4” come in both a hex washer head and a flat Phillips countersunk head while the large diameter cement anchor screws come only with a hex washer head.
Masonry Hole Diameter
The diameter of the hole that needs to be drilled into the base material is slightly smaller than the designated diameter of the cement anchor screw being installed. The hole must be drilled with a carbide tipped bit that meets ANSI standards and is used in a hammer drill. The hammer drill must be set in the hammer and rotation mode. The hole tolerance is critical for the cement anchor screw to obtain minimum holding values in the cement.
Cement Screw Anchor
| Diameter of Cement Screw Anchor | Diameter of Hole in Base Material |
|---|---|
| 3/16” | 5/32” |
| 1/4” | 3/16” |
| 3/8” | 5/16” |
| 1/2” | 7/16” |
| 5/8” | 1/2” |
| 3/4” | 5/8” |
Hole in Fixture Being Mounted
The hole in the fixture being mounted to the masonry material must be larger than the designated diameter of the cement screw anchor being installed in order to ensure clearance for the tapping threads that will embed in the cement.
Cement Screw Anchor
| Diameter of Cement Screw Anchor | Hole Size Fixture |
|---|---|
| 3/16” | 1/4” |
| 1/4” | 3/8” |
| 3/8” | 1/2” |
| 1/2” | 5/8” |
| 5/8” | 3/4” |
| 3/4” | 7/8” |
Depth of Hole
The hole must be drilled to a depth that is 1/4” deeper than the screw will penetrate the base material and is deep enough to meet minimum embedment requirements. This extra space at the bottom of the hole is important because it allows space for the dust created during the tapping process to fall into and out of the way to ensure proper installation.
Minimum Embedment
The cement anchor screw must be embedded into the concrete a minimum of 1” in order to reach minimum holding values.
Maximum Embedment
Cement anchor screws must not be embedded into the base material further than 1-3/4”. Deeper embedments will create installation problems as well as fastener failure. Installation in the hard abrasive base material may create installation problem at embedments less than maximum embedments.
Determining Length of Screw
The minimum length of cement anchor screw to use for any particular application is determined by adding the thickness of the material being fastened to the minimum embedment depth of 1”. The maximum screw that should be considered is determined by adding the thickness of the material being fastened plus the maximum embedment of 1-3/4”.
How to Install
- Drill proper size hole in cement using an ANSI standard carbide drill bit in a hammer drill set in the hammer and rotation mode.
- Clean the hole in the cement using a wire brush, compressed air or vacuum.
- Insert cement anchor screw through the hole in the fixture and into the hole in the cement.
- With the proper sized driver for the type of head on the cement anchor screw being installed, turn the screw clockwise until the head of the screw is tight against the material being fastened.
As with any anchoring project, it is important to keep safety in mind and follow instructions carefully. Always remember to wear safety goggles, handle all tools with extra care and follow all technical specifications. This article is meant to serve only as a basic explanation of concrete fasteners. Always refer to manufacturer's instructions or consult a contracting expert during any anchoring project.
Article Written By:
Mike Pistorino, Vice-President Operations
Concrete Fastening Systems, Inc. has over 40 years of experience selling concrete fasteners. We can ship out one box or a whole pallet of concrete anchors. Our products are of the highest quality... "your satisfaction is guaranteed". We ship all orders the same day the order is received.